Thermostatically controlled oil burner



May 6, 1941. L Q SELBY- 2,241,326"

THERMOSTATI CALLY CONTROLLED OIL BURNER May 6, 1941. L.' o. sELBYfTHERMosTATIcALLY coNTRoLLED 011. BURNER s sheds-sheet 2 Filed Oct'. 9,1936 May 6, 1941. L Q. sELBY 2,241,326

THERMOSTATICALLY CONTROLLED O IL BURNER Filed oct. 9, 193e ssheets-sheet 3 Hg. a /79/2 Patented May 6, 1941 Lynn Otis Selby,Hartford, Conn., assignor to The Sparmal Engineering Corporation, acorporav, tion of Connecticut 20 Claims.

My invention relates to thermostatieally lcontrolled oil burners.

It has among its objects to provide an improved thermostaticallycontrolled oil burner and one especially adapted to use in refrigeratorsof the absorption type. A further obj ect is to provide an supplyingfuel to the burner of such a refrigerator having a movable valve elementdirectly actuatedby the thermo-responsive element to in- ApplicationOctober 9, 1936, Serial No. 104,808

`improved 'thermostatically controlled valve for v crease the supply offuel to theburner upon expension of the thermo-responsive element anddecrease the supply upon contraction thereofln a new and improvedmanner. A still i'urtherA object is to provide an improvedthermostatically controlled valve for controlling a distillate burner.

Another object is to provide such an improved valve especially adaptedfor use in an absorptiontype refrigerator and having, in a unitarystructure withthe temperature controlled valve, both improved high andlow flame adjusting means.

A still further object is to provide an improved ,thermcstaticallycontrolled valve of the plunger type in which the thermally expansibleelement is supported directly on the valve housing. Another object is toprovide an improved thermostatically controlled valve in which .the highand Fiig. 5a is a plan view of the valve of Fig- Flg. 6 is a full sizesectional elevation of another modiiled valve construction:

Fig. 7 is a section on line 'i-I of Fig. 6;

Fig. 8 is a section on line 8 0 of Fig. 6;

Fig. 9 is an elevation, partly in section, of a construction, applicableto any of the above modied forms of valve. for connecting the valveplunger to the expansible fluid operated member of the thermostat; i f

Fig. 1o is a. fun size seccional elevation of sun anlother modifiedthermostatically controlled va ve;

y Fig. 11 is an elevation of the plunger assembly of the valve of Fig.10; y 4 Y Fig. 12 is a sectional detail on line Il -il of Fig. 1o; Fig.13isafu1l size other n'iodied form trolled valve;

Fig. 14 is an elevation of the plunger assembly of the valve of Fig. 13,and

tional elevation of an- Fig. 1e is a dei-.an view somewhat similai-4 toFig. 9V showing a connection suitable'for use with the valve forms shownin Figs. 10 and 13.

low flame adjusting means are concentric with the temperature controlledvalve. Other objects. are .to provide an improved thermostaticallycontrolled valve which can be cheaply and easily thermostaticallycontrolled valve, certain of.

manufactured. which occupies a minimum of space, and which can beinstalled in the limited space available in existing refrigerators ofthe oil burning type in place of the manually controlled valves now inuse.' These and other objects and advantages of my improved constructionwill, however, hereinafter more fully appear. In the accompanyingdrawings I have shown for purposes of ilhmtraticn several embodiments whmy invention -may assume in practice. f these drawings- `Figure 1 is anelevation partly in section .of an oil fburning refrigerator equippedwith my ignprovement, only' those parts of the refrigerator being shownwhich are necessary to an understanding of the invention;

' Fis. 2 is a full size sectionaly elevation of the thermostaticallycontrolled valve of Figure 1; Fig. 3 is a section on line I-lof Figure2;

Fig. 4 ls a section on line H of Figure 2 with Y certain parts omitted;Y

In these drawings, I have shown for purposes of illustration severalforms of my improved which were disclosed and claimed in an application,Serial No. 75,991, filed April 23, 1936. of which the presentapplication is a continuation ln part. In all of the various formsshown, my

improved valve A is adapted to control a distillate' type oil burner B-of a well known Serveltrefrigerator. indicated generally at C, andincluding Fig. 5 is a full size sectional elevation 'of a modified formof thermostatieally controlledv valve;

the usual lboiler, or generator. I, freezing unit 2. fuel supply tankwland co tant level oat chamber! provided with a co er 4a. all in suchmanner as' hereinafter described to enable improved rsults to beobtained never before obtainable ln an oil burning refrigerator.

In this well known BerveP construction. oil from the tank` lis suppliedthrough feed line l to chamber l and the oil is maintained at a`constant level 4b in chamber I' by means of ya usual float valve lgoverned by a noat'l. the usual safety trip bucket l and reset lever..-being provided. The fuel is led from the constant level chamber'l tothe car-bon leg il of the Aburner through a feed line I I having a usualgravity 0P- erated high temperature cut-off valve il controlled by afusible link il located adjacent the` burner B. The chamber ,4 is alsoprovided on one -side wall with a generally cylindrical valve hous-`thermostaticaily coni by means of which the fuel supply tothe burner y Bwas governed.

In accordance with the present invention, the improved thermostaticallygoverned control valve A for automatically regulating oil flow to theylburner B is adapted to be threaded into passage I6, this valve Aincluding an improved valve and thermostatically controlled meansassociated therewith in an improved manner and both of the samecooperating lto enable an improved automatically operative temperatureresponsive control to be obtained for the firstl time in a refrigeratorof this type.

In Figures 1 -4, Ihave shown a preferred form of my improvedthermostatically controlled valvel A. As shown most clearly in Figures2, 3 and 4, the valve casing I1 comprises a piece of cylindrical stock,the lower end I 8 of which is reduced in diameter and threaded to bereceived in the passage I6 at the bottom of the oil well I5,` a suitablegasket I9 forming a fluid tight closure for the oil well at this pointand preventing fluid communication, with the main oat chamber 4 exceptthrough the valve, as hereinafter explained. The valve casing I1 isprovided with a vertical plunger passage 20 terminating sometion 2|.This passage bisects an intersecting horizontal passage 22 whichcommunicates at one end with the well I and at its other end with theiioat chamber .4' through a series of passages 23, 24 and 25, as isshown most clearly in Figure 2. The cross sectionl of the passage 22 isvaried by a vertically reciprocable plunger 26 which is adapted to bereciprocated in the plunger passage 20 by expansible fluid actuatedmeans hereinafter described.

In this preferred form, the plunger 26 includes a generally cylindricalportion 26a having a. close 'running t in the plunger passage 20. Anannular groove 21 is-provided near the lower end of portion 26a forminga control portion 28 at `the lower end of the plunger which is normallylocated in they transverse passage 22, as/,lshown in Figure v2, andcontrols t he passagef-'fof fluid through the valve as tl'f""annular'groove 21 is moved more or less Into register with the passage Theplunger 26 has a reduced upper end portion 30 threaded at 3l and formingan upward1y facmgrshouider s2 located within the threaded portidn 2I ofthe valve casing I1. The shoulder 32 cooperates with the lower end of athreaded sleeve 33 which surrounds and guides the upper end oftheplunger. Sleeve 33 is formed with an upper hexagonal portion 34 topermit rotation of the sleeve to adjust the sanie verti- A needle valve36 is screw threaded intoA a passage 31 aligned with passage 23 in thevalve casing I1 and intersects the horizontal passage 22. The passage31and the needle valve 36 are of somewhat larger diameter than passage23, thus providing a seat 31a (Fig. 4) a't the. upper end of the latterpassage for the tapered end of the needle valve. A hexagonal upper endportion 38 is provided for the rotation of the needle valve 36 foradjusting the same relative to its seat, thereby to establish themaximum flame adjustment for the burner.

The reciprocation of the plunger 26 in the plunger passage is governedby expansible fluid operated means including an expansible wafer 40, theupper end 4I of which carries a exible supporting diaphragm 42 which hasits periphery clamped by screws 42a between upper and lower complementalhousing and supporting members 43 and 44. The expansible wafer 40 isaccurately centrally located within the housing by the provision of anupstanding annular flange45 on housing member 44 within which thediaphragm 42 is closely received. The lower housing member 44 is formedwith a depending cylindrical boss 46 having an axial passage in which abushing 41 is located. 'I'he upper housing member 43 is also providedwith an axial bushing 48 in which is threaded a stud 49 which, uponrotation in one direction, bears at its lower end on the hollow boss 56formed' on the upper end wall 4I of the expansible member and fiexes thediaphragm 42 downwardly, thus depressing the wafer 40. The stud 49 isformed with-an octago- 1 what above the lower end o'f the casing andhavlng a slightly enlarged threaded upper end pornal head which isreceived in an octagonal recess in an externally cylindrical member 5Isecured to the stud by an axial screw 5Ia. Manual rotation ofy the stud49 to control the position of the c expansible member 46 is accomplishedby a rotatable 'control button 52 movable over a suitable dial locatedon the refrigerator and a control cable 53, cooperating stops 53a and53h being provided on the member 5I and casing 43 to limit the rotationof the stud.

'Ihe expansible member 46 is of a well known type adapted to contain anexpansible fluid and communicates through a tube 54 extending into thehollow boss with a temperature responsive element 55 located in therefrigerator compartment adjacent the cooling unit 2. It will'beunderstood that the tube 54 and-temperature responsive element 55likewise contain expansible iluid and that the expansion and contractionof the fluid in elementv 55 is conveyed to and inuences the expansiblemember 40. The plunger 26 is directly connected 'to the lower end wall56 of the expansible member.i To this end the lower wall 56 thereof hasan integral depending stem 51, guided in the bushing 41, which isprovided cally to vary the point at'which the shoulder 32 with a screwthreaded recess .56 to. receive the threaded portion 3| of the plunger.A knurled adjusting wheel 59 is initially threaded onto the plunger 26and is fixed thereto by a lock nut 60 so that rotattion of the wheel 58will rotate the plunivrferl relative to the stem 51 and adjust theplunger vertically relative to the wafer 4|).v

The expansible member 40 and its, housing are supported above theplunger and in `axial alignment therewith by means of -a tubularsupporting member 6I having a portion of its sidewall in termediate itsends cut away to permit access to thewheel 59 and the high and low flameadjustments. The tubular member 6I `has an enlarged lower end portion6Ia which fits over a reduced cylindrical portion 62 at the top of thevalve casannees ing I1 and preferably is secured permanently thereto asby soldering or welding. The outer surber 3|, a screw 34being providedto prevent relative movement of the parts. As shown most clearly inFigure 3, an opening 33 is provided in the lower hexagonal portion Blapermitting access to the set screw 33.

As` shown'most clearly in Figure 2, a ball and socket connection 33 isprovided between the plunger rod 33 and the portion 23a thereof,although this may be omitted if care is taken in the manufacture andassembly of th'e `valve. Here vit should also be noted that to preventbinding of the valve plunger the passage in the low flame adjustmentsleeve 33 is slightly larger than the valve stem33, thus eliminating'anytendency for the plunger to bind due to mlsalignment of the expansiblemember and its support.

- 'I'he plunger 23 is limited in its upward movethe lower end of the lowllame adjusting. sleeve 33 previously referred to, the latter beingvertically adjustable in the plunger passage 23 to vary the upperlimitof movement of the plunger. As'shown most clearly in Figure 2, adefinite relation exists between the shoulder 32 on the plunger and thelower shoulder 23 formed by the groove 21, these shoulders being soarranged that the engagement of the lower end of sleeve 33 with shoulder32 takes place when the control portion 23 of the plunger has almostcompletely ment by the engagement `of the shoulder 32 with proaching thepoint at which it completely closes this passage, the sleeve 33 beingadjusted to permit only a low ame orifice. It will also be underswodthat the adjustment of the needle valve 33 relative to the s'eat 31adetermines the4 maximum volume of oil which can pass through passsge 22and thus constitutes the maximum llame adjustment of the-valve.

In the operation of this preferred form of my improved Valveconstruction, it will be evident that oil is maintained in the constantlevel chamber 4 at the level 4b which is sufilciently high to admit oilto the burner base but is below the top of the burner groove 31 so thatflooding of the burner is impossible, even if the burnershould go out.Also itwill be clear that, as determined by the position of the plunger23 in the plunger passage 23, oil will be supplied from chamber 4through the passages 23, 24 and 23 past the needle 33 of themeteringvalve throughv passage 22 and annular groove 21 to the oil well 'I3 fromwhich the oil is supplied to the burner through feed line Il. 'I'hemaximum flow of oil is determined by the setting of the needle-valve 33and the mini` a pilot flame is maintained in the burner.

'In the position ofthe parts shown in Fig. 2,

'the control button 32 is in the defrost position. -marked 0" on thedial, and consequently the stud 43 is in its uppermost position inwhichthe diaphragm 42 is relaxed and wafer 43 is elevated toenabletheshoulder 32 on plunger 23 to engagethe lowerend of lowflameadjusting sleeve 33,- although the temperature responsive element 33 isat room temperature and wafer 43 is expanded. Defrosting continues withthe burner B remaining on minimum flame until the control button 32 isrotated'to an advanced position on the dial to cause stud 43 to depressthe wafer 43 and with it the plunger 2,3. Assuming that control button32 is rotated toits other extreme position, marked "5 on the dial, whichrepresents the lowest temperature at which it isv supplying the -burnerB with the 'maximuml amount of oil as determined by the setting of themetering valve 36. As the temperature in freezing unit 2 is lowered, thewafer 4will con-Y tract and shoulder 32 will ultimately engage `the istop provided by sleeve 33, when the burnerwill burn with only a pilotflame. It will be understood that rotating the button 32 to anintermediate position on the4 dial will result in the enga'gement ofshoulder 32 and sleeve 33 at a relatively higher temperature in therefrigerator compartment. Y I

It will be evident from the above description that to install myimproved thermostatically controlled valve A in existing refrigerators,it is only necessary .to remove the manually controlled metering valvehitherto in use from the oil well I3 and replace it with the improvedvalve above described.

In adjusting the valve, the metering valve 33 is rst adjusted lwith aplunger 23 depressed so that groove 21 registers with the outlet passage22. In making this adjustment, the needle valve 33 is turned back awayfrom seat 31a until the burner is supplied with the maximum amount of-oil which it can consume without smoking. The

plunger is then released and the low llame ad justment is made byturning the sleeve 33 until it engages theshoulder 32 at a point whenthe shoulder 23 is slightly below the point of cutoi'f, permitting onlya minimum flow of' oil to the burner suillcient to maintain a pilotflame. The wheel '33 is then adjusted relative to the stem 31 to obtainthe proper` temperature setting for the thermostat. It will be evidentthat both the high ilame and low flame adjustments can be varied in thisconstruction without affecting the adjustment of the plunger by wheel 53relative to the expansible wafer 43. Y

In Figures 5 and 5a I-have shown a modified construction in which avalve casing Ila is pro-l vided, generally similar to casing I1, and inwhich the high and low flame adjustment means and the oil passagethrough the valve are similar but wherein the expansible member 43 hasits supporting diaphragm 42 clamped between two annular rings 33 and 33which are rotatably supment over the plunger, a clamping nut 13e beingprovided on the upper end of the standard 13 which when loosened permitsthe expansible member 4 3 and its supporting means to be swung laterallyout of the way andpermit withdrawal Iof the plunger.4 In thisconstruction there is no expansible member. Instead, an anvil 1| is ad`justably screw threaded to the upper end of the plunger, thus providingfor varying the temperaturesetting, the plunger rod having a flattenedportion 12 which enables the rod to be held and the anvil 1| .rotatedrelativejthereto. A compression spring 18 surrounding the plunger bearsat its lower end on the upper end of the low flame adjusting sleeve 88and at its upper end on the anvil 1| fixed to the plunger, thusconstantly urging the plunger against the expansible member-40.

In Figures 6, 7, and 8, I have shown a modified form of valve which maybe used if desired. In this modified construction, the inlet passage 25in valve casing |1b communicates directly with the plunger passage 20and the plunger portion 28a isprovided at its lower end with an axialpassage 14 which communicates with a transverse passage 15, the ends ofwhich-terminate in the groove 21. Also in this construction a spring 13ais located beneath the plunger and acts against a shoulder 18 at thebottom of the plunger passage for constantly biasing the plungerupwardly into the position shown inv Figure 6 in which the shoulder 82engages the lower end of the low flame adjusting sleeve 88. Theoperation of this valve will be obvious from the description of thepreviously described forms. l

In Figure 9 I have shown a modified construction which is applicable toany of the above forms of valve by which the upper screw threaded Aendof the reciprocable plunger can be directly connected by a ball, andsocket joint to the lower end of the expansible member 40. As shown inV88a and is adapted to be a close but free running iit in the bore 80.The plunger 83 is also formed with an annular enlargement 90intermediate lts ends providing a shoulder 9| which cooperates with thelower end of an externally screw threaded sleeve 92 in which the plungerhas a free running t. The sleeve 92 has a hexagonal head 82a |by whichit is adjusted vertically in' the upper screw threaded portion 8| of thevalve v casing I 1c.

A metering valve is provided in the axial passage of plunger 88comprising a stem 93 which is reciprocable in the upper enlarged portion81 and a reduced needle portion 84 which cooperates with the valve seat88a, a spring 95 located 4 in the passage 81 between the spring seat 81aand the shoulder 88 on valve stem 98 constantly biasing the latter intoengagement with a cam' surface 91 on a transversely adjustable pin 98which is threaded at 98a into the valve plunger 88. The pin 98 isprovided with a radial spoke 99 Iby which it is rotated to move the camsurface 91 laterally and adjust the needle 94 relative to seat 86a,andis also provided with a fixed head |00 which prevents accidentalremoval of the pin. The axial passage in plunger this figure, the lowerend wall of the expansible 1 In Figures 10-12 I have shown stillanother.

modified form of my improved thermostatically controlled valve A. Asshown most clearly in Figure 12, the valve casing IIc comprises a pieceof hexagonal stock, the lower threadedend I8 of which is provided with asmall axial inlet passage 25 which communicates with an enlarged axial.bore 80' threaded at its upper end at 8|. The

passage 80 constitutes a vertical'plunger passage which communicateswith the float chamber 4 through passage 25.l The valve casing I1c alsohas a lateral oil passage 82 below the oil level 4b which communicateswith the well I5 and the cross section of which is varied by thevertical reciprocable plunger, shown most clearly in Figure 11, as thelatter is vreciprocated in' passage 80.

In this form of valve the plunger comprises a generally cylindricaltubular member 88 having an axial passage therethrough vcomprising avlower portion 85 of small diameter lforming a valve seat 88a. anintermediate portion 889i slightly increased diametenand an upperportion 81 of still greater diameter providing an up wardly facingshoulder or spring seat 81a. A

lateral passage 88 is provided in the plunger intersecting the axialpassage therein just above the seat 88a and terminating in an externalan- 88 is threaded at its upper end t0 receive a vertically adjustableanvil |0I, a lock nut |0|a being provided to holdy the anvil in adjustedposition.

It will be evident from the above description that an oil passage isprovided through the valve from float chamber 4 through the axialpassages 25 and 85, and the transverse passages 88 and 82 to the wellI5. It will also be evident that as the plunger 83 is reciprocated inthe' The reciprocation of plunger 83 is governed byv the expansiblemember 40 as described in connection with Figure 5, a. spring |02located in the bore 80 beneath the plunger constantly urg- `ing theplunger 88 upwardly into position to en- .gage the shoulder 9| with thelower end of the low flame adjusting sleeve 92, as described inconnection with previous forms.

In Figures 13 and 14 I have shown a modified form of concentric valvewhichmay be used if desired. In this modied lconstruction the -valvecasing I1c is the same but the plunger asits upper end. A lock nut |05ais provided for clamping the valve |08 in adjusted position. To assistin holding the plunger during adjustment of the metering valve |03',diametrically opposed flat portions |08 (Figure 14) are provided at theupper end of the plunger adjacent the clamping nut |05a. A verticallyadjustable anvil |01 is erators.

l pl'OceSSeS.

threaded into the upper end of the valve |03 and engages the wafer 4.0.

The operation of the valve of this modified construction-is similar tothose above described, thehigh llame adjustment being made by rotatingthe metering valve I 03 in the screw threaded passage I I of the plungerand the low flame adjustment being made by rotating they abutment sleeve92.

In Figure 15 I have shown a, construction for directly connecting theplunger to' the expansible member 40, somewhat similar to that shown inFigure 9 except that the ball carrying member corresponding to member'I8 to `Figure 9 is externally screw threaded to take the place ofanvils IIJI and |01 of Figures 10 and 13 respectively.

The direct connection of the plunger to thel expansible fluid operatedmember 40 is highly desirable, and for this reason theconstructionsshown in Figures s, 6, 1o and Y13, ln all of which theplunger is actuated in one direction by a spring, are not preferred. Theelimination of the spring against which the expansible member must workwhen expanding, has been found to result in a more sensitive operationof the valve, enabling closer temperature regulation. Further, when aspring is used, the amount of expansible fluid in the element 55 `andmember l0 varies with the tension of the spring against which thememberv 40 mustexpand, thus ref quiring `matching of the spring and theexpansible fluid in the thermostat which is very objectionable from themanufacturing standpoint and altogether eliminated in my preferreddirect connected plunger constructions.

IIt will be evident that as a result of my invention itis possible forthe first time to provide automatic temperature governed fuel controlfor oil burning refrigerators in which it has been hitherto necessary touse manual fuel control.

Attention. is vfurther directed to .the fact' that `this new result isobtained while enabling the` burner to operate effectively at alltemperatures lwhlleobtaining' certain of the improved results set forthin my vcopending applications and `without irregularities in theviiamesuch as would illustrative purposes and that the invention may be modiedand embodied in other forms without departing from its spiritor thescopev of the appended claims.

What 4I claim as new and desire to secure by v for operating said valvemember, and manually operative valve means disposed longitudinally ofsaid casing having a control portion inside said casing also controllingIthe amount of fuel which can besupplied through said transverse supplypassage, said valve member and valve means each having adjusting meansextending above the exposed upper end of said lcasing and adjustablefollowing insertion of the latter in said socket.

2. In athermostatlcally controlled valve, an axially elongated valvecasing insertable longitudinally in a substantially correspondinglongitudinal socket and having an exposed upper end, said casing hayinga lower fuel inlet and a communicatingtransverse fuel supplypassageextending transversely therein, Vtemperature responsive means forcontrolling, the quantity of fuel supplied through said passageincluding an expansible iiuid operated member and a movable valve memberextending inside said casing and adjustable longitudinally thereof, bysaid member to control'the effective cross section of said transversesupply passage,said valve memberhaving result from the use of. a dripfeed or devices requiring the raising and lowering of the oil supply.Further, as a result of my improved valve constructions, a unitarythermostatically controlled valve structure is provided including thetemperature responsive control valve and the high flame metering valve,which is adapted to be substituted for the manually controlled valvefurnished withexisting oil burning refrig- It .will also be noted thatin various of the improved constructions above described the fuelcontrolvalvegis actuated directly by and moved with the expansible memberduring ex'- pansion and contraction of the, latter, increasing thesupply of fuel to the burner as the ex' pansible member expands. It willy,also be evident that in certain forms of my improved constructionIhave provided such a unitary valve structure inwhich the metering4 andtemperature controlled valves are concentric and which is adapted to,-bey manufactured quickly and cheaply by well known automatic screwmachine improved construction will, however, be apparent to thoseskilled in the art.

Thesefand other4 advantages of my` means adjustable from the upperyexposed end of said casing for limiting the movement of said movablevalve member in one direction whereby to maintain `a minimum fuelsupplythrough said transverse passage, and a metering valve `dis posedlongitudinally of said casing having a control portion within saidcasing and also having a portion outside said casing adjustable fromsaid end of said casing for adjusting said control portion to limit thequantity of fluidwhich can be i supplied through said supply passage.

3. In a thermostatically controlled valve, `an axially elongated casinginsertable longitudinally in a substantially corresponding longitudinalsocket andA having anexposed upper end, said casing having a lower -fuelinlet and a. communieating transverse fuel supply passage extendingtransversely therein, temperature responsive means at one end of saidcasing for controllingl the quantity of fuel supplied through saidpassage including an expansible uid operated member and a plungeroperated'by said member and intersecting said transvilrse supply passageand having a reduced portion adjacent its'lower end forming a shoulderonsaid plunger above the lower end ofsaid plunger adapted to be movedacross said transverse supply 4passage to vary the effective crosssectional area thereof, and means disposed above the exposed upper endof. said casing and adjustable following insertion of said l, casing insaid socket for, limiting the-amount of While I have "minis applicationspecifically described several embodiments of my invention,l it will beunderstood that these are shown for fuel supplied through said passage,and means likewise projecting -above the upper end of said casing andindependently .adjustable relative to said plunger for insuring aminimum orifice in said supply passage.

4. In-a thermostatically controlled valve, an

tudinally in a substantially corresponding longitudinal socket andhaving an exposed upper end,

said casing having a lower fuel inlet and a communicating transversefuel supply passage extending transversely therein, temperatureresponsive means for controlling` the quantity of fuel supplied throughsaid passage including an expansible uid operated member and a valveplunger extending inside said casing and adjustable longitudinallythereof and having a controlling portion inside said casingadapted to bebrought into and out of register with said supply passage in response tomovements of said plunger, and an axial sleeve adjustably carried by theexposed upper end of said casing through which said plunger is movableand located be- .tween the upper end of said casing and said expansibleuid operated member and engageable with sai'd plunger for limiting themovement of said plunger in one direction whereby to maintainraminimum'uid flow through said communicating passages.

5. In combination, a constant level fuel chamber having a verticallyelongated socket, valve mechanism for controlling the ow therefromincluding an axially elongated valve casing insertable longitudinallyinto said socket with its lower end inluid communication with saidchamber below the level of fuel therein and its upper end projecting-above the top of said chamber, said mechanism having an axial inletpassage, an outlet passage and an intermediate transverse fuel supplyes. e all located below said level, temperature responsive means forcontrolling the supply of fuelthrough said supply passage including anexpansible :duid operated member locatedl above theupper end of said`valve casing and a valve member movable therewith and extending insidesaid casing to vary the eil'ective cross-section of said supply passage,'manually operable valve means having a control portion inside saidcasing for limiting the amount of fuel which can be supplied throughsaid supply passage, means on the upper projecting end of said valvecasing for effecting axial adjustment of said valve member, and meansalso accessible from the exposed upper end of said valve casing foradjusting Vsaid valve means while said mechanism remains in saidchamber. v

6. In a thermostatically controlled valve, an

i axially elongated valve casing inserta-ble longi- -municatingtransverse fuel supply passage and a plunger passage` intersecting saidtransverse supply passage, a valve plunger in said plunger paslaxiallyelongated valve casing insertable longiplurmer and also accessible foradjustment at theexposed upper end of said valve casing followinginsertion of the latter in the socket.

7. In a thermostatically controlled valve, an axially elongated valvecasing insertablevlongitudinally in a substantially correspondinglongitudinal socket and having an exposed upper end, said casing havingan axial fuel inlet and a communicating transversely extending supplypassage at one end thereof, two control passages located alongside eachother in said casing and both intersecting said supply passage, amanually adjustable metering valve in one of said control passagesprojecting above the upper exposed end of said casing and at its otherend controlling said supply passage, and an expansible fluid actuatedvalve member in the other controlpassage having a portion movableacrosssaid supply passage to govern the effective cross-section thereofin response .to temperature changes affecting said expansible fluid.

8. In a thermostatically controlled valve, an

axially elongated valve 'casing insertable longi tudinally in avsubstantially corresponding longitudinal socket and having an exposedupper end, said casing having `an axial fuel inlet and a communicatingtransversely extending supply passage at one end thereof, two controlpassages located along-side each other infsaid casing and bothintersecting said supply passage, a manually adjustable metering valvein one of said control passages having its lower end movable into saidsupply passage and having its upper end projecting above the exposedupper end of said valve casing, and an expansible fluid actuated valvemember inthe other control passage having a portion movable across'saidsupply passage to vgovern the eil'ective cross-section, thereof inresponse to temperature changes affecting said expansible fluid, andmeans located at the upper ex municating transversely. extending supplypassage therein adjacent its lower end, a plunger passage intersectingsaid supply passage, a plunger reciprocable in said plunger passagehaving a portion movable across said supply passage to control theeffective cross-section thereof, an exsage having anl annular ygrooveintermediate its ends, -an expansible fluid actuated memberlocated aboveand actuating said plunger to bring its groove into and out of registerwith said transverse passage in said casing, adjustable means located onthe'exposed upper end of said casing El; a metering valve located insaid pansible uid .operated member acting on the upper end of saidplunger having a supporting frame, a manually adjustable metering valvealso controlling the cross section of said transverse supply passage anddisposed inparallel relation to said plungenand .projecting above theexposed upper end of said valve casing, and a rigid support for saidframe carried by the exposed upper end of said valve casing and havingan axial pas. sage' therethrough into which said plunger and meteringvalve project.

10. In a thermostatically controlled valve, un

axially elongated valve casing insertable longitudinally in asubstantially corresponding longiing the effective length of saidplunger, a manually adjustable metering valve also controlling the crosssection of said supply passage and disposed in parallel relation to saidplunger and 'projecting above the exposed upper end of said valvecasing,

land a rigid support for said frame surrounding said plunger andmetering valve and lcarried by said valve casing and having a portioncut away between said valve casing and supporting frame Yto permitaccess to the upper end of said metering valve and, to said adjustablemeans.

11. In a thermostatically controlled valve, an axially elongated valvecasing insertable longitudinally 'in a substantially correspondinglongitudinal socket and having an exposed upper end, said casing havingan axial fuel inlet and a communicating transverse supply passagetherein adjacent its lower end, a plunger passage inter secting saidsupply passage, a plunger reciprocable in said plunger passage having aportion movable across said supply passage to control the effectivecross section thereof, an expansible fluid operated member acting onsaid plunger having a supporting frame located above said plunger,adjustable means carried by the exposed upper end of said valve casingand concentric with said plunger for limiting the extent of movement ofthe latter in one direction. and a rigid support for sive meansV forcontrolling the supply of fuel through said passage including anexpansible iiuid operated member and a vvalve member movable therewithto control said passage, and a metering valve within said valve memberalso controlling the supply of fuel through said supply passage.

15. In a thermostatically controlled'valve having a fuel supply passagetherethrough, temperature responsive means for controlling the supplylof fuel through said passage including an-expansible fluid operatedmembery and a plunger movable with said member to vary the effectivecross-sectional area of said passage, and a metering valve including amanually adjustable valve i member within and coaxial with saidplungeralso said frame carried by said valve casing and surrounding saidplunger and adjustable means and having a portion cut away to permitaccess to said adjustable means.

12. In a thermostatically controlled valve, an elongated'valve casinghaving a supply passage therein adjacent its lower end, a plungerpassage intersecting said supply passage, a plunger reframe, adjustablemeans located between said frame and said valve casing for varying theeifective length of said plunger, a metering valve also controlling thecross-section of said supply passage, and a rigid support surroundingsaid plunger and connecting said frame and valve casing having anintermediate portion cut away to permit access to said metering valveand said adjustable means. v

13.'In a thermostatically controlled valve, a valve casing having atransverse fuel supply passage therein, a plunger passage intersectingsaid supply passage, a valve plunger movable in said plunger passagehaving a portion adjacent its lower end controlling the effective crosssection of said supply passage, low name adjusting meanscoaxial ,withsaid plunger and extending above the latter for limiting the upwardmovement of said plunger and maintaining a minimum orifice in saidsupply passage, and expansible iiuid ac tuated means supported abovesaid plunger for moving said plunger away from said low flame adjustingmeans to increasethe cross section of said supply passage in response toincreases in temperature affecting said iluid.

14. In a thermostatically controlled valve having a. fue! supplypassage, temperature responadjustable to vary the supplyA of fuelthrough said supply passage.

16. In a thermostatically controlled valve having a fuel supply passagetherethrough, temperature responsive vmeans for controlling the supplyof fuel through said passage including an' expansible fluid operatedmember and a plunger reclprocated by and movable in the same directionwith said member to vary the effective cross section of said passage,said plunger having a vertical passage and a horizintal passagecommunicating with said supply passage, and means coaxial with saidplunger and extending into said Vvertical plunger passage for limitingthe amount of fuel supplied through said passage.

17. In a thermostatically controlled valve, a valve casing having alateral oil supply passage and a plunger passage extending transverselyAof said supply passage, temperature responsivemeans controlling saidsupply passage including an expansible fluid operated member and aplunger reciprocable in said plunger passage in response to expansionand contraction of said member and having fluid passage means thereinadapted to be brought into register with said supply passage to controlthe fluid supplied there through, and a manually adjustable needle valvecarried by said plunger and controlling the cross section of said fluidpassage means.

18. In a thermostatically controlled valve, a valve casing havingalateral oil supply passage and a plunger passage extending transverselyof said supply passage, temperature responsive means controlling saidsupply passage including an expansible fluid operated member and aplunger reciprocable in said plunger passage in response to expansionand contraction of said member and having uid passage means thereinadapted to be brought into register with said supply passage to controlthe fluid supplied therethrough, -a needle valve carried by said plungerand` vertically reciprocable relative thereto to vary the cross sectionof said fluid passage means, cam means for reciprocating said needlevalve,` and manually operable means external of -said plunger foractuating said Vcam means.

19. In a thermostatically controlled valve, a

valve casing having a transverse oil supply passage and a verticalplunger passage extending transversely of the same, temperatureresponsive means controlling saidsupply passage including an expansiblefluid operated member and a plunger reciprocable in said plunger passagehav- 'ing communicating vertical and transverse passages, the latteradapted to be brought into register with said supply passage to controlthe fluid flow through. the latter, a needle valve adjustable crosssection of said passage, and means for ad. justing said needle valveincluding an operating member located transversely of said plunger abovesaidneedle valve and having cam means within the vertical plungerpassage acting on said needle valve.

20. In a thermostatically controlled valve, a valve casing having atransverse oil supply passage and a vertical plunger passage extendingtransversely of the same, temperature responsive means controlling saidsupply passage including an expansible iluid operated' member and aplunger reciprooable in said plunger passage having communicatingvertical and transverse passages, the latter adapted to be brought intol.register with said supply passage to control the fluid flow throughthe latter, a needle valve ad-l

